Air conditioning devices are well known, which will both heat and cool air. Typical examples are the well known air conditioning units which will cool and dehumidify outside air passed therethrough, or air recirculated therethrough within a room. Such devices may also include a heating coil for use in the seasons when cooled air is not desired.
These known units are placed in a mode manually by an operator and may include a thermostat which merely amounts to a rotary selector between maximum heat and minimum heat, and the operator must select between recirculation and introduction of fresh air. Additionally, these known units may be operated only in a ventilation mode to supply fresh air without heating or cooling, or to exhaust air from a room.
Some large systems (not window) may also sense the temperature of the outside air and utilize this as a function in controlling a heating, air conditioning, and ventilation system. However, this is usually done only in large central control systems.
The present invention provides a new and improved heating, air conditioning and ventilating system which provides more efficiency as a window type unit, and utilizes larger quantities of outdoor air and therefore improves ventilation, and also lowers operating costs by utilizing a special air sampling technique.